Phylogeny and Classification

Plecoptera, very primitive insects sometimes described as "flying Thysanura," probably had their origins in the Lower Permian period from a stem group, the plecopteroid assemblage, that included the extinct Paraplecoptera and Protoperlaria (Illies, 1965). Some pale-oentomologists assigned some of the Permian fossil Plecoptera to recent families, though Zwick (1981) considered this incorrect, representatives of the latter not appearing in the fossil record until the Eocene (or possibly the Cretaceous).

Stoneflies traditionally were placed in two suborders, Filipalpia (Holognatha) and Setipalpia (Systellognatha). Illies (1965), however, considered the extremely primitive Southern Hemisphere families Eustheniidae and Diamphipnoidae sufficiently distinct from the remaining Filipalpia that they should be grouped in a separate suborder, the Archiperlaria. Both Hennig (1981) and Zwick (1981) argued that Illies' arrangement was not soundly based, and Zwick (1980,1981, 2000), whose classification is followed here, proposed that the stoneflies could be divided into an exclusively Southern Hemisphere group (suborder Antarctoperlaria) and a predominantly Northern Hemisphere group (suborder Arctoper-laria), the separation and subsequent evolution of the two groups resulting from the breakup of the Pangean landmass (into Laurasia and Gondwanaland) during the Jurassic period. A few Arctoperlaria occur in the Southern Hemisphere, presumably as a result of secondary invasions. Figure 7.1 provides a suggested phylogeny for the order.

Suborder Antarctoperlaria

In Zwick's classification this suborder includes the superfamilies Eusthenioidea (families EUSTHENIIDAE and DIAMPHIPNOIDAE) and Gripopterygoidea (AUSTROPER-LIDAE and GRIPOPTERYGIDAE). Illies (1965) considered members of the small family Eustheniidae, which is restricted to eastern Australia, New Zealand, and Chile, to represent the prototype of plecopteran organization. They are large, colorful insects having wings with numerous crossveins and an anal fan in the hind wing with eight or nine anal veins. Larvae are carnivorous and have four to six pairs of abdominal gills. The Gripopterygidae is a large family (about 150 species) mostly found in Australia, with a few species in New Zealand and South America. The adults are mostly dull in color; the larvae, which are sluggish and typically found under rocks and debris in fast-moving water, have a tuft of gills around the anus. Larvae of a few species are terrestrial and lack gills (Zwick, 2000).

Suborder Arctoperlaria

Zwick (2000) divided this suborder into the infraorders Systellognatha and Eu-holognatha. The former contains the superfamilies Perloidea (families PERLODIDAE,

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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